In a traditional paint spray booth, residual paint spray, or overspray, is transported for scrubbing in an appropriate air scrubber arrangement. Such air scrubbers generally include paint overspray collection systems in which the overspray falls through a perforated floor of the paint spray booth and is funnelled through a venturi system. The venturi system accelerates the overspray air speed considerably to effectuate thorough mixing of overspray particles with scrubber water for eventual separation of paint particles and water from the overspray atmosphere in one of a number of methods.
More particularly, in a typical overspray scrubbing system, paint falls through a floor grating and onto flood sheets before entry into the scrubber system. However, some paint particles adhere to the floor grating although the majority of particles pass through the floor grating. Over time, these paint particles tend to adhere to each other and accumulate in icicle-like formations suspended beneath the floor grating. These accumulations of paint either fall off or are power washed from the floor grating. After being dislodged from the floor grating, the paint accumulations often proceed to either stick to the flood sheets and block the water feed to the scrubber venturi or move to the scrubber venturi where they create blockages. Furthermore, although a majority of the paint overspray particles passing through the floor grating funnel through the venturi, some larger paint overspray particles do not funnel through the venturi and fall onto the flood sheet instead. These denser particles also potentially accumulate and either adhere to the flood sheet or move to the scrubber venturi where they may inhibit water flow.
A number of paint application systems currently use water based paints in the spray booths. Such applications make it desirable to collect overspray scrubber water in an overspray collector in order remove paint from the overspray scrubber water. Such paint recovery systems require a relatively pure mixture of paint overspray and water and become less effective when dirt, dust, and other debris fall through the floor grating and onto the flood sheets where they are removed along with the overspray by the scrubber water. Accordingly, it is desirable to provide an air scrubber which collects overspray for separation of paint particles from air while preventing accumulated paint, dirt, dust, and other debris from contaminating the overspray air mixture.